BSAP抑制器和激活器功能的依赖于BSAP度
J J Wallin1, E R Gackstetter, M E Koshland
1Immunology Division, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA.
Science (New York, N.Y.)
|April 16, 1998
概括
在B细胞免疫反应期间,转录因子BSAP选择性地使用激活器功能. 它的抑制功能通过一种依赖于度的机制来缓解,具有动机上下文,不结合亲和力,确定BSAP.
科学领域:
- 免疫学 免疫学 免疫学
- 分子生物学分子生物学
- 转录因子法规转录因子法规
背景情况:
- B细胞的免疫反应涉及复杂的基因表达的调节.
- 转录因子BSAP (也称为Pax5) 在B细胞的发育和功能中起着至关重要的作用.
- 了解BSAP的双重激活器和抑制器功能是如何控制的,是解读免疫反应的关键.
研究的目的:
- 在B细胞免疫反应期间,研究控制BSAP激活器和抑制器功能的选择性向的调控机制.
- 确定结合亲和力与DNA基因背景在决定BSAP功能输出的相对重要性.
主要方法:
- 对BSAP与其激活剂和抑制剂基因的结合亲缘关系的分析.
- 试验性操纵,包括在调节元件中交换激活器和抑制器动机.
- 评估BSAP在动机上下文改变后的功能后果 (激活与抑制).
主要成果:
- 在免疫反应过程中,BSAP保持了激活器功能,而其抑制器功能在免疫反应过程中被选择性地缓解.
- 确定了一种依赖度的机制,其中BSAP激活器基因表现出比抑制器基因的结合亲和力高出20倍.
- 激活器和抑制器动机的交换表明,周围的DNA上下文,而不仅仅是结合亲和力,决定了BSAP是否作为激活器或抑制器.
结论:
- BSAP的功能结果主要取决于其结合位点的特定DNA序列背景,重于简单的结合亲和力差异.
- 这种上下文依赖的调节提供了一个复杂的机制,用于在免疫激活过程中微调B细胞基因表达.
- 这些发现突出了转录因子活性控制的新层,这对适应性免疫至关重要.
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